The present invention relates to an ink jet recording apparatus which ejects ink drops, in accordance with print data, from the discharging orifices of the print heads onto a recording medium, so that ink dots are arrayed, as defined by the print data, on the recording medium.
In the ink jet recording apparatus (referred to also as ink jet printer), a power switch, an on-line switch for connecting the printer to and disconnecting from a host, a cleaning switch, and the like are provided on the case of the printer, as disclosed in Examined Japanese Patent Publication No. Hei. 7-57551. The cleaning switch is used for the forcible cleaning of the print heads. As well known, the print head is provided with discharging orifices for discharging ink in the form of ink droplets. The ink at the discharging orifices is sometimes dried and solidified, so that the printer is possibly inoperable for printing. In this case, it is necessary to remove the dried and solidified ink. To this end, the cleaning switch is operated to drive the cleaning unit incorporated into the printer, whereby the print heads are forcibly cleaned by the cleaning unit.
When a paper jam occurs during the printing operation or when the user finds that the paper size or the print data is wrong, it is necessary to forcibly stop the printing operation. To this end, the user operates the switch or switches in an exceptional manner, to thereby stop the supply of data from the host to the recording device or the printer. An example of the exceptional switch operation is to simultaneously operate a plural number of switches.
When the user who is not accustomed to the operation of the printer is put in such a situation, he tends to take an action to stop the power switch or pull the plug of the power cord, in order to forcibly stop the power supply to the printer. Immediately after he removes the jammed paper or replaces the papers with other papers of correct size, he turns on the power switch.
The ink jet printer is constructed such that when the power switch is turned on, the cleaning operation is automatically executed, to prevent the nozzle blocking problem, irrespective of the paper supply process, initializing process, the length of the rest time. In the cleaning operation, the print heads are capped with the capping members, and in this state the suction pump is operated to forcibly suck ink from the print heads. If the rest time of the printer is too short to cause the nozzle blocking, the cleaning operation is automatically performed. The cleaning operation consumes much ink and time. This leads to wasteful use of ink and places the user in a long time waiting.